Conventional towers, pylons, and the like, for carrying cables for electrical transmission across the country have, typically, splayed or parallel legs with relatively large footprints and have connecting cross-members, formed of steel members. Such structures are heavy and take a relatively long time to erect, repair and the like. Replacement in whole, or in part, can take significant amounts of time. In an emergency, when a plurality of such towers are structurally damaged or the cables thereon snapped by the effect of ice build-up due to, e.g. freezing rain, this can cause very serious disruption to the transmission of electricity, throughout a community or larger area.
Recently, alternative tower structures have been introduced as temporary or permanent replacements of the aforesaid steel towers, which replacement towers are formed of aluminum, have a smaller footprint and are faster and easier to erect on site than aforesaid steel towers. These towers are provided in hollow, modular form and are erected from hollow modular units, generally, on site, by the bolting of one modular unit to another unit to the desired height.
Each of the modular units are essentially rectangular in shape and, generally, formed by the welding of four identical angled panels at adjoining vertical edges to form a box of desired height, breadth and width, typically, 2.5 m×41 cm×41 cm. Relatively large apertures are provided in each of the aluminum sides to offer savings in material and weight while allowing of wind passage.
Such towers have been found to be most structurally sound, lightweight and extremely fast to erect as to offer significant beneficial emergency situation remedial units.
The full tower may be assembled on the ground and raised by means of a crane or helicopter, or built piecemeal in the air by means of a Jim pole assembly technique, to the desired height.
However, there remains a need of the aforesaid aluminum modular tower to minimize on the amount of material used, while improving on the structural strength of the tower.